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Item Nitrogen and Phosphorus Related Functional Genes Enhance Nutrient Removal in The Integrated Aquaculture Wastewater Bioremediation System in The Presence of Photosynthetic Bacteria.(Springer, 2024-12-20) Ramzan, Muhammad Naeem; Shen, Ding; Wei, Yingzhen; Emmanuel, Arslan; Nicholaus, Regan; Yang, Wen; Zheng, ZhongmingIntegrated Aquaculture Wastewater Bioremediation Systems (IAWBSs) are crucial for treating nutrient-rich mariculture water. However, there is a lack of detailed information about the functional mechanisms between nitrogen (N) and phosphorus (P) functional genes and the bacterioplankton community in the presence of photosynthetic bacteria (PSB). This study evaluated the connections between N and P functional genes in IAWBSs under the influence of PSB. The results showed significant improvements in effluent quality, with removal efficiencies of 79, 74, 83, 90, and 71% for NO2 −−N,NO3 −−N, PO4 3−-P, NH4 +−N, and CODmn, respectively. Adding PSB enhanced and altered microbial diversity within the system, promoting the abundance of functional genes related to N and P cycling. Notably, genes associated in denitrification (nirK and nirS), ammonification (ureC) and amoB, involved in nitrification, were significantly increased after PSB was added. Furthermore, genes such as phnK, phoD, and phoX, which are involved in P transformation, also showed increased abundance levels. These genes were closely linked to the microbial community distribution, species diversity, and nutrient cycling. Microbial community changes can result in changes in functional gene abundance. This study provides important and novel insights for developing bioremediation strategies for polluted sites. This demonstrates the fundamental relationships between the IAWBSs’ functional units and the distribution of microbial communities under the influence of PSB.Item Relationship between Forest Biodiversity Attributes and Potential Carbon Stocks in Dry Tropical Reserve Forests of Assam, Northeast India(University of Latvia, 2021) Malunguja, Gisandu K; Thakur, Bijay; Devi, AshalataPotential forest carbon stocks are significantly correlated to forest biodiversity attributes such as diversity, density, and richness. However, there is little such information on dry tropical reserve forests of Assam, a state in northeast India. We studied this relationship in two reserve forests. Pearson correlation, cluster analysis, and regression analysis were used to explore these relationships. The estimation of plant carbon stocks was made using both destructive methods for herbaceous and non-destructive allometric methods for trees. The most dominant plant species in the Bhomoraguri reserve forest were Cynodon dactylon, Datura stramonium, Clitoria ternatea, and Tectona grandis for grasses, forbs, climbers, and trees, respectively. Cymbopogon nardus, Colocasia esculenta, Mikania micrantha, and Shorea robusta, were dominant species in the Balipara reserve forest for grasses, forbs, climbers, and trees, respectively. The presence of Lantana camara, Smilax ovalifolia and Piper betle in the studied forests suggests disturbed ecosystems. Other observed species such as Aristida spp., Cenchrus spp., Ipomoea cheirophylla, and Sida spp. are indicators of disturbed ecosystems as well. The biomass stock differed significantly among plant growth forms. Carbon stocks were 302.93 and 283.97 t ha–1 in the Bhomoraguri reserve forest and Balipara reserve forest, which were equivalent with 555.87 and 521.30 t ha–1 of CO2 sequestration, respectively. Tree species contributed the greatest amount (54.80%), followed by forbs (21.36%), climbers (19.35%), and least for grasses (4.49%). Correlation analysis indicated a strong positive relationship between the density of trees and climber species with carbon stock potentials, suggesting that increase of their density favoured carbon sequestration in forest ecosystems. Diversity of grasses was negatively correlated with potential carbon stock in the examined forests. The unique contribution of each group to carbon stock was 91.8, 58.01, 51.3, and 11.11% for climbers, trees, grasses, and forbs, respectively. Thus, it is important to examine biodiversity attributes in estimation of forest carbon stocks.Item Awareness, Habitats and Population Status of the Endangered Rungwecebus kipunji in Mt. Rungwe Nature Reserve, Tanzania(MUST Journal of Research and Development, 2022) Ojija, Fredrick; Maijo, Simula P.; Mwidege, AsheriThe Mount Rungwe Nature Reserve in Tanzania is a significant ecological area that protects the endangered Rungwecebus kipunji. The goal of the study was to analyze the ecological habitat and population of R. kipunji in Mount Rungwe Nature Reserve. During our study, we recorded 412 (mean: 41.2 ± S.E: 5.7) R. kipunji individuals in the reserve. The R. kipunji population was found in a comparatively low abundance at sites with a significant number of anthropogenic activities. Human activities were observed to occur less frequently (χ2 = 40.76, p = 0.0001) inside the nature reserve (n = 33, 17.19%) than outside and/or along the border zones (n = 159, 82.81%). Respectively, the peeling of tree bark and firewood collection were the most common anthropogenic indicators found inside and outside the forest reserve. We also found that >40% of male and > 30% of female respondents were aware of R. kipunji’s presence. We found that 30% of female and 32% of male respondents had previously received conservation education. In comparison to other age groups, >25% of respondents aged > 45 years old claimed to have already learned about R. kipunji. Furthermore, 48% of the respondents claimed that Mount Rungwe Nature Reserve helps them live by providing fuelwood and building materials. People aged 31–43 and > 43 years old collect fuelwood and building materials, respectively, while those under 31 years old collect food resources. In summary, our findings imply that, to improve R. kipunji, local residents surrounding the forest reserve should be made aware of the species to reduce anthropogenic activities within and along the reserve's buffer zones. Thus, our findings suggest that the R. kipunji populations and habitat quality in Mount Rungwe Nature Reserve could be used as a benchmark for the conservation of other endangered species elsewhere.Item An Assessment of the Current Status and Regeneration Potential of the Traditional Conserved Forests (Ngitili) in Kishapu District, Tanzania(TROPICAL PLANT RESEARCH, 2020) Malunguja, Gisandu K.; Rubanza, Chrispinus K. D.; Devi, AshalataThe current study was carried out in the community forests conserved under the indigenous knowledge known as “Ngitili” in Kishapu district of Tanzania. The aim was to assess the current status and determines its regeneration potential in terms of plant species diversity, herbaceous productivity and tree stocking. A field survey was conducted for recording the current status while the phytosociological was carried to recognize vegetation composition and diversity. Regeneration potential was determined based on the population size of seedlings, saplings and adults. Disturbance index was used to calculate the level of disturbances while herbaceous productivity and tree stocking were estimated based on allometric models. Descriptive statistics for quantitative data was analysed using SPSS version 20. The study recorded a total of 10 Ngitili in Kishapu district, out of which, 9 still existing but highly threatened and disturbed, only 1 Ngitili was recorded to be dead (not existing). A total of 66 plant species were recorded of which 20 were grasses, 18 were forbs, and 28 species (17 genera and 13 families) were trees and shrubs. The dominant grass species were Aristida funiculata (28.9%) and Cynodon dactylon, while Monechma debile (4.6%) was the dominant forb. Similarly, Acacia drepanolobium (45.4) and Balanites aegyptiaca (42.9) trees dominated the area. The majority of tree species exhibited a “not regenerating” condition (51.8%) only a few (2.11%) showed a “good regeneration” condition while “newly regeneration” condition recorded 0.00%, with a diversity ranging from 1.86–2.44. Herbaceous and tree stocking potential was 1.23±0.05 t DM ha-1 and 5.66±0.21 t Cha-1 respectively, with a standing stem density (stems ha-1) of 512.07±193.86. The study observed great degradation of the Ngitili characterized by low diversity and poor regeneration conditions. This signified that these community forests are currently threatened and its sustainability is highly at risk unless strong initiatives take place.Item Towards Agricultural Sustainability: Status and Distribution of Copper in Usangu Agro-Ecosystem, Tanzania(ELSEVIER, 2022) Mng’ong’o, Marco; Munishi, Linus K.; Ndakidemi, Patrick A.Despite the positive role of copper (Cu) in plants and animals, excessive amounts have environmental and health effects. Cu has been excessively accumulating in agricultural soils worldwide due to increased agrochemicals and wastewater use in farming. The increased Cu concentration in soil negatively impacts soil microbes and plants, affecting crop productivity and environmental quality. Here, the status and spatial distribution of Cu in Tan- zanian agro-ecosystem were characterized as its information are currently missing. The study assessed 198 soil samples from 10 irrigation schemes and 3 land use, where total and bioavailable Cu were determined and contamination status assessed. The variable Cu status and distribution were observed among studied land use where paddy farming areas had higher total (5892.36 μg/kg) and bioavailable Cu (3342 μg/kg) than total and bioavailable Cu concentration in maize farming areas (total Cu 1522.09 μg/kg and bioavailable Cu 779 μg/kg) and conserved areas (total Cu 4415 μg/kg and bioavailable Cu 3267 μg/kg). The bioavailability of Cu for plant uptake was 52% in maize farming areas, 49.9–63.5% in paddy farming areas, and 48.4–51.6% in reserved areas, where farming areas had higher Cu bioavailability. Contrary to other agro-ecosystems worldwide, all Cu concentration values studied in the Usangu agro- ecosystem are within the acceptable limit (100000 μg/kg). However, this should not have to be taken for granted or ignored; there is a need to set strategic management to maintain Cu levels in agro-ecosystem within acceptable limits to ensure environmental quality, food safety, and sustainability.Item The Critical Role and Application of Microbes towards Sustainable Development and Human Wellbeing(EAST AFRICAN NATURE & SCIENCE ORGANIZATION, 2022-08-08) Ojija,Fredrick; Mng’ong’o ,Marco; Mayowela, FaridaMicroorganisms (also called microbes) make up a large portion (1 trillion (1012) species or 60%) of the Earth’s living as they are abundant and diversified in nature. Though they are vital for ecosystems and human welfare, their roles are often ignored or underrated. While most studies are underway in the global north to figure out how to utilise microbes in agriculture, industries, medical, space mission, and many other sectors, this kind of research is limited in the global south, particularly in Sub–Saharan Africa. Also, there has been scarce knowledge regarding the importance of microorganisms. The present paper aims to highlight and discuss current knowledge on the roles and/ or applications of microorganisms and their contribution toward sustainable development and human welfare in the global south. It also aims to help the scientists and/ or researchers in sub Saharan Africa comprehends the use of microbial communities. We reviewed 84 published original research and review articles to explore microbial roles and their applications. We establish that many microbes play critical roles, which include but are not limited to ecological, pharmaceuticals, food source, biofuel or energy production, drugs or medicine development, nitrogen and carbon fixation, biocontrol agents, bioremediation, decomposition of organic matters, and soil formation. Since microbes potentially ensure the functioning of the Earth’s ecosystem and support human welfare, research on this subject should be prioritised in the global south to improve human development and well-being.Item The Essential Oil From the Spices and Herbs Have Antimicrobial Activity Against Milk Spoilage Bacteria(African Journal of Agriculture and Food Science, 2022-03-24) Ahmed, Amina; Mdegela, Robinson H.Spices and herbs are usually added to milk to impart a particular flavour and medicinal purposes. Moreover, it is reported that additional spices and herbs extend the shelf life of milk. Contemporary use of essential oils from spices and herbs show promising results against various food spoilage microorganisms. Therefore, the essential oils from the spices and herbs from Zanzibar were used to assess antimicrobial activity against milk spoilage bacteria. The essential oils were extracted using steam distillation by a Clevenger apparatus. Minimum inhibitory concentrations (MICs) were determined by the microdilution method. All the extracts from cardamom, cinnamon, ginger, and lemongrass showed antimicrobial activity against Streptococcus thermophillus, Lactobacillus plantarum, and Escherichia coli. The essential oils exhibited higher antimicrobial activity than gentamycin. The MICs ranged between 0.004 and 0.125 µg/µl. Therefore, spices and herbs added to milk have the potential to inhibit the growth of milk spoilage bacterial.Item People’s Knowledge and Perceptions Towards Bee–Pollinators in the Southern Highlands, Tanzania: Conservation Implications and Strategies(SAGE, 2022) Ojija, Fredrick; Leweri, CeciliaBackground and research aims: Bees are important pollinators of flowering wild plants and agricultural crops that contribute significantly towards food security, improving people’s livelihoods, and maintaining genetic diversity in plant communities. However, the decline of the bee population due to anthropogenic changes and limited knowledge of bees is threatening bee diversity, particularly in sub–Saharan Africa. Negative perceptions, that is, fear and disgust, are common emotions that lead to a lack of support for bee conservation. Understanding local people’s perceptions is vital as it can help in bee conservation decision making and proper protection actions. Methods: We conducted the study in the Mbeya and Songwe regions of Tanzania to assess the knowledge and perception of local people about bee–pollinators and conservation using a structured questionnaire Results: Wefoundthatthemajority ofrespondents (91%) haveheard about bees(χ2=6275,p<0.001)andtheirconservation initiatives (71%), and about 84% of respondents consider bees to be important (χ2 = 168.9, p = 0.001). Moreover, Apis mellifera had the highest identification rate, with 52.7% of respondents. A binary logistic model revealed that respondents’ knowledge of bee–pollinators and pollination is not influenced by their age (except for respondents aged 15–18 years, p = 0.012) and education level. While 74% of respondents claimed to be afraid of bees, 79% stated that bees are dangerous to humans. The most common cause is personal experience with bee stings. Poor farm management practices, for example, use of fire and deforestation, were noted by 79% of respondents as the most human activities threatening bee–pollinators. Conclusion: Overall, the respondents were more familiar with A. mellifera compared to non–Apis bee species. Implications for conservation: Thus, we suggest that implementation of pollinator management programs is vital to ensure their survival and reduce the perceived threat by dispelling myths and encouraging interest in bees.Item Potentially toxic elements status and distribution in Usangu agroecosystem-Tanzania(Elsevier, 2021-07-03) Mng’ong’o, Marco; Comber ,Sean; Munishi, Linus K; Ndakidemi, Patrick A; Blake, William; Hutchinson, Thomas HThis study was conducted to highlight status and distribution of potentially toxic elements (PTEs) in Usangu agroecosystem-Tanzania. The study involved 198 soil samples from 10 irrigation schemes including three land use. The concentrations of selected PTEs (Cd, Cr, Cu, Pb, Zn, As, Hg, Co, Nie etc.) were determined to estimate status, distribution, and contamination hierarchy. The total and bioavailable PTEs were determined by aqua regia digestion and Mehlich 3 methods, respectively. We observed variable total PTEs concentration (in mg/kg) among land use and irrigation schemes such as Cr (15), Co (2.9), Fe (7371), Mn (263), and Zn (18.2). Also, concentration of other PTEs (in μg/kg) were As (1382), Cd (22), Cu (3342), Hg (3.3), Ni (4107), and Pb (5661). It was observed that 99.5, 87, 66 and 12% of the studied soils had total Fe, As, Se and Hg concentration above allowable threshold in agricultural soils, respectively. The bioavailable PTEs fraction were lower than total values from different land use and irrigation schemes, higher values of bioavailable PTEs were associated with agricultural intensifications. The status of PTEs in Usangu agroecosystem observed to be at level potentially to cause damaging effect to soil invertebrates, plants, animals and human if remain unregulated. This study highlights baseline information and evidence for site-specific environmental management planning and a scientific basis required to establish PTEs management in agricultural soils to ensure health food and environmental safety.Item Allelopathic Effects of Sphaeranthus suaveolens on Seed Germination and Seedling Growth of Phaseolus vulgaris and Oryza sativa(Hindawi, 2021-02-15) Laizer, Hudson C; Chacha, Musa N; Ndakidemi, Patrick AWeeds with allelopathic effect have been reported to cause significant damage in agriculture particularly in smallholder farming systems. ,is study assessed the allelopathic effects of different concentrations of crude extract of a noxious weed Sphaeranthus suaveolens on seed germination and seedling growth of Phaseolus vulgaris and Oryza sativa by examining germination, seedling height, and total chlorophyll content after seven and fourteen days of crude extract treatment, respectively. Results showed that seed germination and seedling growth were significantly (p<0.001) decreased with increase in concentration of crude extract, signifying concentration dependency. Highest concentration (100%) of S. suaveolens crude extracts resulted in 90% and 100% inhibition of P. vulgaris and O. sativa seed germination, respectively. Chlorophyll content, fresh weight, and root and shoot length of both P. vulgaris and O. sativa were also significantly (p<0.001) affected by highest concentration (100%) of S. suaveolens crude extracts. Results from this study suggest that the extract of S. suaveolens contains water-soluble allelochemicals which significantly reduce growth and productivity of P. vulgaris and O. sativa.Item Effect of lactic acid fermentation, boiling and soaking on selected nutrients and health promoting components of mango seed kernels(INNSPUB, 2020-12-12) Runyogote, Joseph; Chacha, Musa; Ndabikunze, Bernadette; Raymond, JofreyMango seed kernels are considered as wastes although they are rich in essential nutrients and bioactive compounds for human health. Lack of commercial application (unlike oil seeds) presence of antinutrients, difficulty in processing and little information on nutritional and functional values contribute significantly to their underutilization. These factors underscore the need for processing these seeds to enhance their utilization as food or functional food. The purpose of this study was to investigate which processing technique was capable of improving selected nutrients and bioactive compounds, and reduction of the antinutritional factors to acceptable levels. Selected vitamins, minerals and antinutrients, antioxidant activity and total phenols were determined using standard methods. All the processing methods at different set conditions significantly (p<0.05) reduced the antinutritional factors of the mango seed kernels to above 38%. The results showed that, lactic acid fermentation had no significant differences in all analyzed minerals while boiling and soaking reduced the contents of the minerals except for potassium and zinc on soaked samples. The maximum percentage increase of total phenolic content, antioxidant activity and ascorbic acid was observed in samples fermented with Lactobacillus plantarum and their values were 25%, 37% and 28% respectively. On contrast, boiled and soaked samples had a significant decrease in ascorbic acid and antioxidant activity and all employed processing techniques showed insignifant variations of α-tocopherol content. The results in this study indicated that lactic acid fermentation reduced the antinutrients to acceptable levels and improved the studied nutritional and bioactive compounds as compared to boiling and soaking methods, thus considered as a technique for processing mango seed kernels for functional foodsItem Patterns of Fish Community Structure in Protected and Non-Protected Marine areas of Mainland Tanzania(WIO Journal of Marine Science, 2022) Salema, Fausta G; Mbije,Nsajigwa E; Mwakalapa, Eliezer B.,; Rija, Alfan A.Information on the benefits of Marine Protected Areas (MPAs) for the condition of fish stocks is not well documented in Tanzania. Fish landing sites located in Tanga and Mtwara regions were surveyed to assess patterns of fish community structure; particularly fish abundance, species diversity, growth patterns, and maturity stages, based on catches landed at sites with different protection status. Fish abundance in the catch from protected areas was significantly lower than in non-protected areas (p=0.002). Species diversity was relatively higher in catches from non-protected (H=2.742) compared to protected areas (H=2.232). A high percentage of species (63.24 %) exhibiting negative allometric growth was observed in catches from non-protected areas. Further, a large number of mature fish was observed in catches from protected areas compared to non-protected areas (p<0.01). These indices are useful indicators of the performance of MPAs. The observed negative allometric growth and reduced number of mature fishes in non-protected areas suggest that extractive pressure and disturbances from fishing gears have negative impacts on the fish stock. Continued high extraction may induce a decline in general fish size due to the constant selection for large-trait fish specimens, potentially causing evolutionally change in morphological traits. In contrast, the lower abundance and species diversity from the protected areas reflected low catch effort as a result of regulated fishing pressure in MPAs, rather than indicating the actual diversity in the fish stocks in these protected waters. Based on these findings it is recommended that more regulatory strategies are implemented in non-protected waters to allow more time for fish to attain appropriate harvest sizes and to ensure the effective protection of marine resources.tItem Impact of climate change on biodiversity and food security: a global perspective—a review article(BMC, 2021-03-03) Fredrick OjijaClimate change is happening due to natural factors and human activities. It expressively alters biodiversity, agricultural production, and food security. Mainly, narrowly adapted and endemic species are under extinction. Accordingly, concerns over species extinction are warranted as it provides food for all life forms and primary health care for more than 60–80% of humans globally. Nevertheless, the impact of climate change on biodiversity and food security has been recognized, little is explored compared to the magnitude of the problem globally. Therefore, the objectives of this review are to identify, appraise, and synthesize the link between climate change, biodiversity, and food security. Data, climatic models, emission, migration, and extinction scenarios, and outputs from previous publications were used.Item Effectiveness and Suitability of Oyster Mushroom in Improving the Nutritional Value of Maize Flour Used in Complementary Foods(Hindawi, 2021-03-16) Siyame, Prisca; Kassim, Neema; Makule, EdnaComplementary foods based on habitual cereals such as maize have been linked with the promotion of undernutrition in young children. Blending the starchy-rich maize with nutritious-rich indigenous food such as oyster mushroom could improve the nutritional composition of complementary foods. This study investigated the effectiveness and suitability of oyster mushrooms in improving the nutritional value of maize flour commonly used as a bulk ingredient in complementary foods. Flour made of well-cleaned and sun-dried oyster mushroom was blended with maize flour at 0% (control), 30%, 40%, and 50%. Proximate composition, mineral density, and sensory evaluation were determined using standard procedures. Significant improvement in the nutritional quality of formulated flour blends with all proportions of mushroom flour was obtained . Blending maize flour with 30%, 40%, or 50% oyster mushroom flour improved the protein content of formulated flour blends from 8.63% to 18.20%, 8.63% to 20.37% and 8.63% to 22.75%, respectively. The increase in ash and fiber content ranged between 82.52% to 84.16% and 50.69% to 58.35%, respectively. Mineral content of formulated flour blends was improved from 62.89% to 64.72% (iron), 7.63% to 22.69% (zinc), 77.48% to 78.02% (calcium), and 67.55% to 67.64% (potassium). Sensory scores of porridges prepared from formulated flour blends showed good acceptance for the colour, flavour, and aroma of the porridges from three formulated flour blends. Overall, this study recommends blending oyster mushroom with maize flour to improve the nutritional content of formulated flour blend for young children who rely on maize porridge as their complementary food.Item Climate change mitigation through carbon dioxide (CO2) sequestration in community reserved forests of northwest Tanzania(Agriculture and Environmental Science Academy, 2020) Malunguja, Gisandu K.; Devi, Ashalata; Kilonzo, Mhuji; Rubanza, Chrispinus D.K.Forests play a key role in climate change mitigation through sequestering and storing carbon dioxide from the atmosphere. However, there is inadequate information about carbon accumulation and sequestered by community reserved forests in Tanzania. A study was carried to quantify the amount of carbon sequestered in two forests namely; Nyasamba and Bubinza of Kishapu district, northwestern Tanzania. A ground-based field survey design under a systematic sampling technique was adopted. A total of 45 circular plots (15 m radius) along transects were established. The distances between transect and plots were maintained at 550 and 300 m, respectively. Data on herbaceous C stocking potential was determined using destructive harvest method while tree carbon stocking was estimated by allometric equations. The collected data were organized on excel datasheet followed by descriptive analysis for quantitative information using Computer Microsoft Excel and SPSS software version 20, while soil samples were analyzed based on the standard laboratory procedures. Results revealed higher carbon sequestration of 102.49±39.87 and 117.52±10.27 for soil pools than plants both herbaceous (3.01±1.12 and 6.27±3.79 t CO2e/yr) and trees (5.70±3.15 and 6.60±2.88 t CO2e/yr) for Nyasamba and Bubinza respectively. The study recorded a potential variation of soil carbon sequestration, which varied across depths category (P < 0.05). However, there was no difference across sites (P >0.05) and species (P > 0.05) for herbaceous and trees. The findings of this study portrayed a significantly low value for carbon stocking and sequestration potential for enhanced climate change mitigation. Therefore, proper management of community reserved forest is required to accumulate more C for enhancing stocking potential hence climate change mitigation through CO2 sequestration offsets mechanism.Item Argemone Mexicana’s Leaf Crude Extract Suppresses Phaseolus Vulgaris And Zea Mays Germination And Growth(Zibeline International, 2023-10-30) Ojija ,FredrickThe Argemone mexicana plant species is invading many habitats in Tanzania. Nevertheless, there have not been many studies to assess how it affects crops. In petri dishes and pot experiments, we investigated the suppressive effects of A. mexicana on Phaseolus vulgaris and Zea mays germination and seedling growth. Different concentrations of A. mexicana leaf (AmL) crude extract was applied to the seeds and seedlings of P. vulgaris and Z. mays. At higher concentrations (>70%), AmL crude extract concentrations reduced the germination and growth of P. vulgaris and Z. mays seeds. The fresh biomass, root lengths, stem diameters, and heights of P. vulgaris seedlings were reduced at higher concentrations (>75%) of AmL, which had a negative impact on their growth vigour. Although this study shows that P. vulgaris and Z. mays germination and growth were inhibited by A. mexicana crude extract, field research experiments should investigate the suppressive effects of this invasive weed on native plant species. The study recommends further management of A. mexicana to protect native biodiversity. It is expected that these results will be helpful in developing policies and programs for managing invasive plants while taking into account the effects on people's livelihoodsItem Characterization of land use influence on soil phosphate bioavailability in Usangu agro-ecosystem-Tanzania(ELSEVIER, 2021) Mng’ong’o, Marco; Munishi, Linus K.; Ndakidemi, Patrick A.Phosphorus (P) is an important nutrient required for plant growth. Land use influences concentration and bioavail- ability of P in agricultural soils. About 198 soil samples (0-30 cm soil depth) were collected from three land-use types (maize, paddy, and conserved areas) in Usangu basin located in Southern Highland Tanzania. The con- centration of soil P determined were compared among different land-use types and locations. The total P (TP), complexed (Po), and bioavailable P (B-P) were measured. The concentration of TP and B-P was determined by acid digestion and Mehlich 3 method, respectivelly, The Po concentration in soil extract was obtained by subtract- ing B-P from TP. TP, B-P and Po concentration in collected soils samples were in range of; Total P (63.12-1350.9 mg/kg), Bioavailable P (0.52-49.87 mg/kg), and complexed P (62.60-1301.03 mg/kg). The cropping area had high TP but very low B-P, especially in paddy farming areas indicating cropping and associated activity decrease bioavailable P in agricultural soils. Furthermore, soils from cropping areas had higher Al, Fe, and Mg concentra- tions than conserved areas, which caused a substantial reduction in B-P due to increased P fixation and adsorption. It is important to note that converting natural land to farming land could potentially influence soil P dynamics thus affecting P bioavailability, crop productivity, and environmental safety.Item Harvest and Postharvest Factors Affecting Bruise Damage of Fresh Fruits(CSHS, 2019) Hussein, Zaharan; Fawole, Olaniyi A.; Opara, Umezuruike L.Fresh fruits are susceptible to bruising, a common type of mechanical damage during harvest and at all stages of postharvest handling. In quest of developing and adoption of strategies to reduce bruise damage, it is of utmost importance to understand major factors influencing bruise susceptibility of fresh produce at these stages. This review presents a critical discussion of factors affecting bruising during harvest and postharvest handling of fresh fruits. Excessive compression forces during harvesting by handpicking or machines, and a series of impacts during harvesting, transport and packhouse operations can cause severe bruise damage. The review has further revealed that bruising is dependent on a number of other factors such as produce maturity, ripening, harvest time (during the day or season) and time lapse after harvest. The susceptibility to bruising is partly dependent on how these factors alter the produce physiological and biochemical properties, and the environ- mental conditions such as temperature, humidity and several other postharvest treatments. Hence, the successful applications of harvesting techniques by use of trained personnel and proper harvesting equipment are essential to reduce both the incidence and severity of bruising. Furthermore, the careful selection of postharvest handling temperature and other treatments can increase resistance of fresh produce to bruise damage.Item Suppressive abilities of legume fodder plants against the invasive weed Parthenium hysterophorus (Asteraceae)(ELSEVIER, 2021) Ojija, Fredrick; Ngimba, ChristopherThe alien invasive plant Parthenium hysterophorus (Asteraceae) has been reported to impend smallholder farmers’ livelihood, and biodiversity conservation in sub-Saharan Africa. While earlier studies reported that the invasion may be supressed if plant density in invaded habitats is sufficiently maintained, only a few quantitative experi ments on competition between legume (Fabaceae) fodder plants and invasive plant species have been conducted. We determined whether three selected test legume fodder species, Desmodium intortum (greenleaf desmodium), Lablab purpureus (hyacinth bean) and Medicago sativa (lucerne), can suppress P. hysterophorus growth. These le gumes were selected because they have been used to suppress various weeds in sub-Saharan Africa owing to their rapid growth, strong root systems, bigger leaf canopy, high biomass production and capacity to form many branches. Also, they are used by livestock as forage when other fodders are dry and become limited. The legume fodder plant species and P. hysterophorus were grown as mono- and mixed cultures in pot experiments. Fifty-day old P. hysterophorus seedlings were harvested to determine any suppressive abilities of the legume species against the invasive. We found that the growth of P. hysterophorus was negatively impacted when grown with two or three test legume species compared with monoculture. Respectively, stem height, total fresh biomass and leaf chlo rophyll content of P. hysterophorus seedling were reduced by >60%, >59%, and >70% when grown in combi nation with all three legume fodder species compared with sole cropping or in mixture with just D. intortum or M. sativa. The results suggest that the selected legume fodder plants have the ability to suppress growth of P. hysterophorus. Further, this study demonstrates the potential importance of using legume fodder plant species in the management of alien invasive plantsItem Experimental evaluation of drying of banana using a double-pass solar collector (DPSC) and theoretical analysis using a CFD model(TAYLOR & FRANCIS, 2020-07-13) Mutabilwa, Philemon X.; Nwaigwe, Kevin N.Preservation of banana through drying is a recommended method for improving the shelf life. In this study, an experimental and theoretical evaluation of a developed forced-convection indirect solar drying system with a double-pass solar collector (DPSC) was undertaken. Experimentation using banana slices of 4 mm thickness was carried out. The DPSC achieved an optimal peak outlet temperature of 72°C with a maximum operational efficiency of 72.5%. A computational fluid dynamic (CFD) model was developed for prediction of the dryer temperature and 3D airflow distribution within the dryer unit using ANSYS 18.2. The CFD model was validated using experimental data and good agreement was achieved. The devel oped dryer demonstrated improved efficiency over similar dryers, and this is attri butable to the unique arrangement of component parts. Dried banana chips were evaluated for quality through taste, color and shape and the results indicated good quality products. This was attributed to the pretreatment of banana chips with lemon juice prior to drying.
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